Microstructure Evolution and High Strength-Ductility Synergy of Ti-13Nb-13Zr-2Ta Alloy Fabricated by Laser Powder Bed Fusion  

作　　者：Libo Zhou Biao Peng Jian Chen Yanjie Ren Yan Niu Wei Qiu Jianzhong Tang Zhou Li Wei Chen Weiying Huang Cong Li 

机构地区：[1]Institute of Energy and Power Engineering,Changsha University of Science and Technology,Changsha,410114,China [2]State Key Laboratory of Powder Metallurgy,Central South University,Changsha,410083,China [3]FIR Metals and Resource,LTD,Zhuzhou,412000,China [4]School of Mechanical and Energy Engineering,Zhejiang University of Science and Technology,Hangzhou,310023,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2024年第12期2029-2044,共16页金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.52205140);the Outstanding Youth Foundation of Hunan Province(Grant No.2023JJ20041);the Science and Technology Innovation Program of Hunan Province(2023RC3241);the Research Foundation of Education Bureau of Hunan Province(Grant No.22A0216).

摘　　要：This work systematically investigates the densification,microstructure evolution and the attainment of high strength-ductility in Ti-13Nb-13Zr-2Ta alloy processed by laser powder bed fusion(LPBF).A narrow and viable process window(P_(laser power)=175 W,v_(scanning speed)=1000 mm/s,h_(scanning distance)=0.1 mm and d_(layer thickness)=0.03 mm)was accordingly determined and the relative density of Ti-13Nb-13Zr-2Ta alloy reaches 99.76%.The depth of molten pool increases gradually with the increase of energy density,and the relationship between the depth of molten pool and energy density has been quantitatively described.Three types ofα′martensites with average grain width less than 3μm can be observed in the LPBF-fabricated Ti-13Nb-13Zr-2Ta alloys,attributed to the significantly high cooling rate and remelting process.The fine grain size,high density dislocations,nanotwins,ordered oxygen complexes andα+α″heterostructure all contributed to the high strength(1037.75±25.18 MPa)and ductility(20.32%±1.39%)of LPBF-fabricated Ti-13Nb-13Zr-2Ta alloy in this work.

关 键 词：Laser powder bed fusion Ti-13Nb-13Zr-2Ta Microstructure Mechanical behavior 

分 类 号：TG14[一般工业技术—材料科学与工程]